Photographic silver halide film element



1970 HARUO TAKENAKA ET AL 3,492,122

PHOTQGRAPHIC SILVER HALIDE FILM ELEMENT Filed April 15, 1966 UnitedStates Patent 3,492,122 PHOTOGRAPHIC SILVER HALIDE FILM ELEMENT HaruoTakenaka, Teppei Ikeda, Toshiaki Okiyama, Sueo Miyazaki, and ChojiHibino, Kanagawa, Japan, assignors to Fuji Shashin Film KabushikiKaisha, Kauagawa, Japan, a corporation of Japan Filed Apr. 13, 1966,Ser. No. 542,242 Claims priority, application Japan, Apr. 16, 1965, 40/22,147 Int. Cl. G03c 1/84 U.S. Cl. 96-84 4 Claims ABSTRACT OF THEDISCLOSURE The disclosure relates to a silver halide film element havinga polyethylene terephthalate film base and coated thereon a co-polyesterlayer under the silver halide emulsion. To the other side of the base isapplied an organic solvent solution of a mixture of a cellulose esterand a copolyester. An antihalation layer is applied which consists of amember selected from the group consisting of styrenemaleic anhydridecopolymer, vinyl acetate-maleic anhydride copolymer, and a maleicanhydride copolymer denatured by a monohydric alcohol having 4 to 12carbon atoms.

The present invention relates to a photographic silver halide material,more particularly, it relates to a photographic film comprising abiaxially oriented, crystallized polyethylene terephthalate film supporthaving an improved anti-halation layer.

Conventionally, anti-halation layers are generally divided into twokinds according to the position thereof. One is where the anti-halationlayer is positioned at the surface of a photographic film opposite tothe side of a photographic emulsion layer. The other is where theantihalation layer is positioned between the support and a photographicemulsion layer. This invention relates to the former type, and thefollowing specification is concerned with this kind of anti-halationlayer, except where there is a specific designation to the contrary.

The anti-halation layer for photographic film must satisfy the followingconditions:

(1) Absorb the light having wave lengths Within the entire range towhich the light-sensitive material is responsive;

(2) Be completely removable, without leaving stains, a suitable treatingbath, such as a pre-treating bath, a developing bath, or a water-rinsingbath;

(3) Have no undesirable effects on the emulsion;

('4) Must have sufficient mechanical properties such as wear resistance,and scratch strength, and flatness;

When the photographic element is rolled up in a state such that theanti-halation layer is in contact with an emulsion layer, theanti-halation layer should not be transferred to the emulsion layer.

An object of this invention is to provide a polyethylene terephthalatefilm for photography having an anti-halation layer satisfying theabove-mentioned factors.

Another object of this invention is to improve the adhesion between thepolyethylene terephthalate film and the anti-halation layer.

Another object of this invention is to provide, after the removal of theanti-halation layer, a substratum of the 'back surface of thephotographic film, said substratum having improved mechanical propertiessuch as wear resistance, and scratch strength, as well as improvedphysical properties such as transparency and flatness, and to providefurther desirable properties to the film after development.

3,492,122 Patented Jan. 27, 1970 Other objects of this invention will beapparent from the following specification and drawing, in which: Abiaxially oriented, crystallized polyethylene terephthalate film supporthas poor adhesive characteristics to other materials. Therefore, whenapplying an anti-halation layer directly to the surface of the film, theadhesive strength of the anti-halation layer to the polyethyleneterephthalate film is insuflicient; therefore, when the film is rolledup with the anti-halation layer being in contact with the emulsionlayer, the anti-halation layer is frequently transferred to the emulsionlayer. This makes practical use of the photographic film very difficult.

As the results of various investigations, the inventors have found thatwhen a layer composed of a mixture of a cellulose ester and a copolyester of terephthalic acid and glycols is formed on the surface of abiaxially oriented, crystallized, polyethylene terephthalate filmsupport as a substratum, and then an anti-halation layer containing amaleic anhydride copolymer binder is applied to said substratum, theanti-halation layer is adhered firmly to the film support.

The polyester used in this invention is preferably a copolyesterconsisting of terephthalic acid and glycols, that is, a ternaryco-condensation polyester consisting of terephthalic acid, ethyleneglycol and triethylene glycol, which is soluble in the solvents andmixed solvent described hereinafter. A typical example is aco-condensation product of 1 mol of terephthalic acid residual group,0.8-0.5 mol of ethylene glycol residual group, and 0.5-0.2 mol oftriethylene glycol residual group.

Further, the cellulose ester used in this invention may be one which issoluble in said solvents and mixed solvents, the compatible range of theweight ratio of the cellulose ester to the polyester being 50:50 to :15in a preferable concentration, capable of providing a stable coatingsolution. Cellulose acetate, cellulose acetate propionate, cellulosebutyrate and the like may be used.

The concentration of the coating solution in this invention maygenerally be in the range of 0.1 to 2%, but the range of 0.1 to 1.0% ispreferable. There are no particular limitations about the degree ofpolymerization of the polyester and the cellulose ester used and it ispreferable to vary the concentration of the coating solution inaccordance with the degree of polymerization thereof.

The solvents used for the coating solution of this invention may becommon industrial solvents. For example, there are alcohols, such as,methanol, ethanol, methyl Cellosolve, and Cellosolve; ketones, such as,acetone, methyl ethyl ketone, and cyclohexanone; esters, such as methylacetate, ethyl acetate, and cellosolve acetate; hydrocarbons, such as,hexane, cyclohexanone, benzene, and toluene; clorinated hydrocarbons,such as, methyl chloride, ethylene chloride, tetrachloroethane, andtrichloroethylene; and cyclic ethers, such as, tetrahydrofuran anddioxane. These may be used alone or in combinations thereof.

Further, it is preferable to add into the abovementioned solvent anorganic solvent capable of swelling, softening and/or dissolvingpolyethylene terephthalate since by the addition thereof the substratumcan be adhered more firm- 1y to the polyethylene terephthalate base.

Examples of organic solvents capable of swelling, softening and/ordissolving polyethylene terephthalate, are phenol, o-chlorophenol,p-chlorophenol, cresol, and other phenol derivatives, benzoic acid,salichlic acid, salicylic acid esters, monochloroacetic acid,trichloroacetic acid, trifiuoroacetic acid, 2-nitropropanol, benzylalcohol, benzaldehyde, acetonylacetone, acetophenone, benzamide,benzonitrile, and methyl nicontinate.

For improving the coating and sliding properties of the film during thecoating procedure, or after developing the film and removing theanti-halation layer, a suitable additive, for example, an anionicsurface active agent, such as, sodium dodecylbenzene sulfonate, sodiumlaurylsulfonate, or sodium N-methyloctyl tauride may be incorporatedinto the coating solution comprising the polymer and the solvent.

The anti-halation layer directly coated and formed on theabove-mentioned substratum according to the process of this invention,is one of a type where the layer is coated using an organic solvent. Inthis case, the binder for the anti-halation layer may comprise analkali-soluble resin, that is, a copolymer of maleic anhydride and avinyl compound co-polymerizable with maleic anhydride. For example,there is a styrene-maleic anhydride copolymer and a maleicanhydride-vinyl acetate copolymer.

The alkali-soluble resin is dissolved in the above-mentioned alcohol orketone in a resin concentration of above and the solution is kneadedwith carbon black or mixed with an anti-halation dye to provide ananti-halation mother liquid. Various additives for improving the coatingproperty, preventing adhesion to the emulsion layer, and controlling thefriction coefiicient are added. Further, a suitable solvent selectedfrom the above-mentioned alcohols, ketones, hydrocarbons, andchlorinated hydrocarbons is added to provide the anti-halation coatingsolution.

By using the maleic anhydride copolymer denatured by one or moremonohydric alcohols having 4 to 12 carbon atoms in the anti-halationlayer, the transfer of the antihalation layer to the emulsion layer canbe effectively prevented. The denature in this specification means theformation of a half ester by opening the ring of the acid anhydridegroup of the maleic anhydride copolymer.

In order to denature the maleic anhydride copolymer, the copolymer isdissolved by heating into the monohydric alcohol having 4 to 12 carbonatoms in an amount of 1.5 to 5 times the weight of the copolymer. Afterthe copolymer has been completely dissolved, a low-boiling point alcoholsuch as methanol or ethanol, or a ketone is added into the solution in acopolymer concentration of to above 5%. The solution is then kneadedwith carbon black or mixed with an anti-halation dye to provide ananti-halation coating mother liquid.

The above-prepared coating liquid is applied on the substratum composedof a mixture of polyester and cellulose ester on a polyethyleneterephthalate film, and dried to provide the anti-halation layer.

An example of the photographic film having the antihalation layerprepared according to the process of this invention as described aboveis shown in the accompanying drawing in its cross-sectional view. On oneside of an oriented polyethylene terephthalate film support, asubstratum 2 composed of a polyester-cellulose ester mixture is formed.The anti-halation layer 4 is then applied. On the opposite side of film1, a first layer 2 composed of polyester is formed. A substratum 3 oremulsion layer is formed by coating a gelatin dispersion onto firstlayer 2. Finally, a photographic light-sensitive emulsion layer 5 isapplied to layer 3.

Since the anti-halation layer is sufiiciently adhered to the supportaccording to the process of this invention, the anti-halation layer isnot transferred by adhesion to the emulsion layer even if the film isrolled up such that the anti-halation layer is in contact with theemulsion layer. Further, since the anti-halation layer, as taught bythis invention, can be removed very easily by processing, it can becompletely removed during the usual de-filming procedure by adding alight-squeezing procedure. Furthermore, after the removal of theabove-mentioned antihalation layer, the substratum as taught by thisinvention, appears on the back surface of the light-sensitive film, and,since the substratum has sufiiciently high wear resistance and scatchstrength, the film can be sufliciently used in practice afterdevelopment.

EXAMPLES The following will serve to illustrate the practical examplesfor the production of a photographic film comprising a polyethyleneterephthalate support having the anti-halation layer taught by thisinvention. These examples, however, are merely explanatory, and shouldnot be construed as limiting the invention.

Example 1 A polyester was formed by adding an ester exchange reactioncatalyst to a mixture of 1 mol of dimethyl terephthalate, 1.7 mols ofethylene glycol, and 0.8 mol of triethylene glycol. Into a mixed solventof parts of ethylene dichloride, 10 parts of phenol, and 10 parts oftetrachloroethane 2 parts of the above-prepared polyester was dissolved.The solution was then applied to one surface of an oriented polyethyleneterephthalate film at 60 C. and dried for 5 minutes at C.

A gelatin dispersion consisting of 1.0% of gelatin, 2.0% of water, 4.0%of acetic acid, 40.0% of methanol and 55.0% of acetone was then coatedinto this just formed layer, and coating was dried for twenty minutes at60 C. (second layer).

Into a mixed solvent of 52 parts of ethylene dichloride, 8 parts ofmethylene chloride, 20 parts of methanol, 20 parts of tetrachloroethaneand 20 parts of phenol, were dissolved 0.2 part of the above-preparedpolyester and 0.2 part of triacetyl cellulose, and the coating solutionwas applied to the opposite surface of the polyethylene terephthalatefilm at 80 C. and dried for six minutes at 100 C. An anti-halation layerconsisting of 1 part of a styrenemaleic anhydride copolymer, 0.25 partof sodium laurylsulfonate, 70 parts of acetone, 30 parts of methanol, 10parts of cyclohexanone, and 1 part of carbon black at 30 C. was coatedonto this layer, and the coating was dried for 20 minutes at C. toprovide the anti-halation layer. Onto the gelatin layer (second layer)on the polyethylene terephthalate film, was coated, as usual, aphotographic silver halide emulsion, and dried. The anti-halation layerhad good adhesive property to the polyethylene terephthalate film, andalso good flatness.

The anti-halation layer was completely removed when the photographicfilm was immersed for 60 to 90- seconds in an usual defilming treatingbath mainly consisting of sodium sulfate, and then rinsed with water.Also, no stain was left. Further, the transference of the anti-halationlayer to the emulsion layer was not observed at a humidity of 80% RH andat a temperature lower than 20 C.

EXAMPLE 2 The procedure as in Example 1 was repeated except that acopolymer of styrene and maleic anhydride was dissolved in 3 parts ofbutanol by heating and the solution was used instead of the copolymersolution in Example 1. In this example, almost the same results as inExample 1 were obtained. Also, no transference of the anti-halationlayer to the emulsion layer was observed at a humidity of 80% RH and ata temperature of 30 C.

EXAMPLE 3 The procedure as in Example 2 was repeated usingmonochloro-acetic acid instead of phenol, with substan tially the sameresults as in Example 2. I

EXAMPLE 4 The procedure as in Example 2 was repeated usingtrichloroacetic acid instead of phenol with substantially the sameresults as in Example 2.

EXAMPLE 5 A polyester was prepared by adding an ester-exchange reactioncatalyst into a mixture of 1 mol of dimethyl terephthalate, 1.3 mols ofethylene glycol and 1.2 mols of triethylene glycol. After dissolving 15parts of the thus prepared polyester into 1000 parts oftrichloroethylene,

the solution was applied to one surface of an oriented polyethyleneterephthalate film at 60 C. and dried for 5 minutes at 80 C. On thusformed layer was applied the gelatin dispersion as described in Example1 followed by drying.

Into a mixed solvent of 52 parts of ethylene dichloride, 8 parts ofmethanol, 20 parts of tetrachloroethane, and 20 parts of phenol, weredissolved 0.04 parts of the polyester as described in Example 1, and0.018 parts of cellulose acetate butyrate, and the solution was appliedto the opposite side of the polyethylene terephthalate film at 50 C. anddried for 6 minutes at 100 C. On the thus formed layer was coated at 30C., the anti-halation layer prepared by dissolving 2.5 parts of astyrene-maleic anhydride copolymer into a mixed solvent of 2.5 parts of=butanol and 2.5 parts of octyl alcohol, adding thereto 0.25 parts ofsodium laurylsulfonate, 90 parts of methanol, 10 parts of acetone, 10parts of cyclohexane and 1.0 parts of carbon black. The layer was driedfor 20 minutes at 90 C.

Finally, a gelatino silver halide photographic emulsion was coated asusual, on the gelatin layer of the polyethylene terephthalate film, anddried.

The anti-halation layer had thus formed high adhesive strength to thepolyethylene terephthalate film base, and also good flatness.

EXAMPLE 6 A polyester was prepared by adding an ester-exchange reactioncatalyst to a mixture of 1 mol of dimethyl terephthalate, 1.5 mole ofethylene glycol, and 1 mol of triethylene glycol. After dissolving 0.7parts of this polyester and 1 part of cellulose nitrate into a mixtureof 150 parts of ethylene dichloride, 50 parts of acetone, 13 parts ofphenol and 15 parts of tetrachloroethane, the solution was applied toone side of an oriented polyethylene terephthalate film at 50 C. It wasthen dried for 10 minutes at 210 C.

Thereafter, a gelatin dispersion consisting of 1.0 part of gelatin,parts of water, 4 parts of acetic acid, 55 parts of ethylene dichloride,10 parts of acetone, and parts of methanol was applied to the abovelayer, and dried for 20 minutes at 100 C.

Further, 0.2 parts of the above-prepared polyester and 0.4 parts oftriacetyl cellulose were dissolved into a mixture of 52 parts ofethylene dichloride, 8 parts of methylene chloride, 20 parts ofmethanol, 20 parts of tetrachloroethane, and 10' parts of phenol, andthe solution was applied on the opposite side of the film at C. anddried for 10 minutes at 100 C.

Into a mixture of 2 parts butanol and 4 parts of lauryl alcohol wasdissolved a vinyl acetate-maleic anhydride copolymer by heating and thesolution was mixed with 2 parts of carbon black, parts of acetone, 20parts of ethanol, and 10 parts of Cellosolve to provide an anti-halationlayer coating solution. The coating solution was applied on theabove-formed layer at 30 C. and dried for 20 minutes at 95 C. to form ananti-halation layer.

On thus formed gelatin layer on the polyethylene terephthalate film wascoated a gelatino silver halide emulsion followed by drying.

The thus obtained anti-halation layer had high adhesive strength to thepolyethylene terephthalate base, and exhibited good flatnesscharacteristics.

These examples conclusively illustrate the advantages of this invention.Having thus described our invention, we claim the following:

What is claimed is:

1. A photographic silver halide light-sensitive element which consistsessentially of:

(A) a support consisting of a biaxially oriented, crystallizedpolyethylene terephthalate film having a photographic silver halideemulsion layer coating thereon;

(B) a substratum on the emulsion side of the film support, saidsubstratum consisting of a copolyester;

(C) a substratum on the opposite side of the filrn support, saidsubstratum having been formed by coating an organic solvent solution ofa mixture of cellulose ester and a copolyester which consists of acocondensation product of 1 mol of terephthalic acid residual group, 0.8to 0.5 mol of ethylene glycol residual group, and 0.5 to 0.2 part oftriethylene glycol residual group, the weight ratio of cellulose esterto polyester being 50:50 to :15, and over said substratum;

(D) an anti-halation layer having incorporated therein, as a binder, amember selected from the group consisting of styrene-maleic anhydridecopolymer, vinyl acetate-maleic anhydride copolymer, and a maleicanhydride copolymer denatured by a monohydric alcohol having 4 to 12carbon atoms.

2. The photographic silver halide light-sensitive element as describedin claim 10, wherein the binder is maleic anhydride copolymer denaturedby a monohydrio alcohol having 4 to 12 carbon atoms.

3. The photographic silver halide element as described in claim 10wherein said maleic anhydride copolymer is selected from the groupconsisting of styrene-maleic anhydride copolymer and vinylacetate-maleic anhydride copolymer.

4. The photographic silver halide element as described in claim 10wherein said denatured maleic anhydride copolymer is obtained bydissolving by heating said maleic anhydride copolymer into saidmonohydric alcohol in an amount of 1.5 to 5 times the weight of saidcopolymer.

References Cited UNITED STATES PATENTS 1 3,178,287 4/1965 Sweet et a1.9684 2,698,239 1/ 1951 Alles et al. 9 2,984,569 5/1961 Huys et a1. 96-87FOREIGN PATENTS 626,241 4/1963 Belgium. 790,023 1/ 1958 Great Britain.

GEORGE F. LESMES, Primary Examiner M. B. WITIENBERG, Assistant ExaminerUS. Cl. X.R. 9687; 260-16

